Neuroscience
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Randomized Controlled Trial
Upper Limb Motor Training Based on Task-Oriented Exercises Induces Functional Brain Reorganization in Patients with Multiple Sclerosis.
The aim of this work was to investigate changes in motor performance and in the brain activation pattern during finger movements, following upper limb motor training in multiple sclerosis. Thirty people with multiple sclerosis with mild upper limb sensorimotor deficits were randomly allocated to one of two groups: the experimental group (n = 15) received an upper limb treatment based on voluntary task-oriented movements; the control group (n = 15) underwent passive mobilization of shoulder, elbow, wrist and fingers. All participants completed three treatment sessions per week for eight weeks. ⋯ However, only the experimental group showed increased lateralization towards more normal brain activation following treatment, with activation clusters mainly located in the left brain hemisphere and right cerebellum. In conclusion, both active and passive interventions were effective in improving motor performance. However, only the treatment based on voluntary task-oriented movements could induce changes in brain activity that may have reflected skill acquisition by the right hand, reducing the activation of compensatory areas and decreasing brain resource demand.
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The present study investigated how pain appraisals from other individuals modulated self-pain anticipation and perception. Appraisals of pain intensity from 10 other individuals were presented before the participants received identical electrical pain stimulation themselves. In reality, the presented other's pain appraisals, with either low or high in mean and variance, were generated by the experimenter, and were randomly paired with the subsequent electrical stimulation at either low or high intensity. ⋯ In contrast, when the mean was high, the higher variance enhanced sensorimotor α-oscillations and suppressed subsequent pain perception. These results demonstrated that others' pain appraisals can modulate both of the anticipation and perception of first-hand pain. It also suggested that the top-down modulation of others' pain appraisals on pain perception could be partially driven by the different brain states during the anticipation stage, as captured by the prestimulus sensorimotor α-oscillations.
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Acute aerobic exercise induces short-term neuroplasticity, although it remains unknown whether biological sex and ovarian hormones influence this response. The present study investigated the effects of biological sex and ovarian hormones on short-term neuroplasticity induced by acute aerobic exercise. Young active adults (n = 17 males and n = 17 females; 21 ± 2 years) participated in two sessions in which transcranial magnetic stimulation (TMS) measures were acquired immediately before and after a 20-min bout of moderate-intensity cycling at 65-70% of maximal heart rate. ⋯ SIGNIFICANCE STATEMENT: Acute exercise induces short-term changes indicative of neuroplasticity within the primary motor cortex and corticospinal pathway. This research reveals that increases in corticospinal excitability and decreases in intracortical inhibition occur similarly in males and females, and that female hormones do not influence these changes. These findings may be used to assist with developing exercise interventions aimed at promoting neuroplasticity in both sexes.
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γ-Synuclein (γ-syn) is expressed by astrocytes in the human nervous system, and increased extracellularly in the brain and cerebrospinal fluid of individuals diagnosed with Alzheimer's disease. Upregulation of γ-syn also coincides with proliferation of glioblastomas and other cancers. In order to better understand regulation and function of extracellular γ-syn, primary human cortical astrocytes were treated with γ-syn conditioned media at various physiological concentrations (50, 100, 150 nM) after cell synchronization. ⋯ Further analysis of cell cycle markers with immunocytochemistry of BrdU and Ki67 after treatment with 100 nM γ-syn confirmed increased initial cell proliferation and decreased non-proliferating cells. Western blot analysis demonstrated increased γ-syn levels after 100 nM treatment at 24 and 48 h, and increased pro-BDNF, mature BDNF and cell viability at 48 h. The results demonstrate that γ-syn internalization by human cortical astrocytes causes upregulation of the cell cycle, followed by subsequent BDNF expression and release.
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Response inhibition is a central aspect of cognitive control. Usually, response inhibition is examined using information from a single sensory modality. Yet, evidence suggests that conflicts between information from different modalities affect response inhibition. ⋯ This also explains why less intense braking processes (reflected by IFG activity) are still able to maintain a reasonable response inhibition performance level. It can be concluded that the tactile and visual domains do not only differ in regard to their efficiency to trigger response inhibition processes but also in their susceptibility to interference while informing inhibitory control. Clinical implications are discussed.